Apparatus for making seamless tubes



(No Model.)

I. G. PLATT.

APPARATUS FOR MAKING SB'AMLESS TUBES.

No. 405,115. Patented June 11, 1.889.

UNITED STATES PATENT OFFICE.

IRVING G. PLATT, OF IVATERBURY, CONNEOTIOUT.'

APPARATUS FOR MAKING SEAMLESS TUBES.

SPECIFICATION forming part of Letters Patent No. 405,115, dated June 11, 1889.

Application filed March 1, 1889. Serial No. 301,640. (No model.)

To all whom it may concern.-

Be it known that I, IRVING G. PLATT,residing at Waterbury, in the county of New Ha- Ven and State of Connecticut, have invented certain new and useful Improvements in Apparatus for Forming Seamless Tubes; and I do declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, which form a part of this specification.

My invention relates to an improved apparatus for rolling seamless tubing, the object being to simplify apparatus for this purpose and secure a superior product at a comparatively low cost.

WVith these ends in View my invention consists in an apparatus having certain details of construction, as will be hereinafter described, and pointed out in the claims.

In the accompanying drawings, Figure 1 is a view, partly in elevation and partly in section, of an apparatus constructed in accordance with my invention and showing the formation of a seamless tube from an ingot, and Fig. 2 is a View of such apparatus in front elevation.

In the apparatus herein shown I employ a mandrel having a breaking-down bevel or taper A, located between and gradually merging into the cylindrical ends B and O of the mandrel, the end B corresponding to the internal diameter of the ingot from which the tubing is to be drawn and the end 0 to the internal diameter of the tubing to be produced. This mandrel is adjustably secured to a rod D, pivotally connected with a fixed support E, which holds it against longitudinal movement. The mandrel is arranged to extend centrally into a chamber formed by the conjunction of two grooves F F, respectively encircling the peripheries of two heavy rolls G G, mounted on shafts H II and rotating in the direction of the arrows I I and therefore away from the larger or butt end of the mandrel, which is adjusted between the rolls, so that its breaking-down bevel will bevirtually includedbetween the points where the rolls first make contact with the ingot and break contact with the tube produced therefrom. A portion of the smaller end of the mandrel will also be included between these two points. By preference, and as shown, the said smaller end of the mandrel extends beyond the point where the rolls break contact with the tube, which is thus supported and carried.

In using my improved apparatus a suitable tubular ingot J is mounted upon the larger end of the mandrel, its end adjacent to the rolls being beveled, so as to permit them to take hold of it. Then when the rolls are started they will draw the metal of the ingot toward and over the bevel of the mandrel and break it down upon such bevel and then re-form it upon the smaller end of the mandrel, which co-operates with the walls of the grooves in the rolls in forming the seamless tube K, which has the internal support of the mandrel while it is under external pressure. It will thus be seen that the bevel virtually forms a drop in that portion of the mandrel over which the metal is broken down by the rolls to which the larger end of the mandrel centrally feeds the ingot, while its smaller end supports the tube while under pressure from the rolls.

If desired, the ingot and rolls, either or both, may be heated to facilitate the drawing of the former. If desired, also, the ingot may be rotated on its longitudinal axis while it is being drawn. I would therefore have it understood that I do not limit myself to the exact construction shown and described.

I am aware that it is not new to make seamless tubes by flat-rolling a tubular ingot and then opening it by forcing it against a pointed mandrel.

Having fully described my invention, what I claim as new, and desire to secure by Letters Patent, is-= 1. In an apparatus for rolling seamles tubes, the combination, with two or more grooved rolls, of a mandrel adapted at one end to support an ingot and made smaller at the other end, which is extended between the rolls to the point where they break contact with the work, whereby a drop is formed in that portion of the mandrel over which the ingot is broken down by the rolls, which are rotated away from the larger end of the mandrel.

2. In an apparatus for rolling seamless tubes, the combination, with two or more grooved rolls, of a mandrel having a breaking-down taper or bevel between its ends, such bevel being Virtually included between the two points where the rolls make contact with the ingot and break contact with the tube and the rolls being rotated from the larger end of the mandrel.

In testimony whereof I have signed this specification in the presence of two subserib- 1o ing witnesses.

IRVING G. PLATT.

Vitnesses:

CHAS. B. SHUMWAY, WM. J. DE MAURIAC. 

